In a principal aspect the present invention relates to a device for testing electric circuits, and more particularly, a hand held circuit testing device which includes various attachments that interact with leads and contacts and wherein the circuit testing device provides a visual, as well as an audio indication of a closed circuit, a polarity, short circuit and battery drain test.
Modem vehicles often include a wide variety of electrical items all powered by a direct current battery. Such items are typically incorporated in low voltage circuits, e.g. 28 volts or less. Often, the wiring in a vehicle is difficult to access and since there may be multiple electrically driven components, circuit checking and circuit testing with respect to each of those multiple components and items is time consuming and complex. Thus, troubleshooting the electrical system of a motor vehicle is often a particularly challenging task.
Consequently, there has developed a need for a device which will enable and facilitate easy testing of circuits in such an environment. Such testing includes the need to identify short circuits, to check circuits from a distance, to check polarity, to check battery drain, and to check whether the circuit is a complete and closed circuit. Often, attempting to check such circuits using a device which operates a light in response to a low voltage current flow is inadequate for diagnostic and vehicle repair situations. Audio responses are often required inasmuch as the light may not be visible to the mechanic. In sum, there has developed an important need for a compact, portable, low voltage circuit testing device or kit.
Briefly, the present invention relates to a circuit testing device which provides both audio and visual indication of a direct current voltage. Te device is in the form, shape and size of a typical heavy duty screwdriver with lead wires and probes project from the opposite ends of the device for connection to wires and contacts associated with a circuit to be tested. Thus, the device includes a hollow handle with an audio buzzer and light subassembly slidably mounted in the handle and with lead probes and/or wires projecting from the opposite ends of the handle electrically connected to the subassembly. When a closed circuit is sensed, a buzzer, as well as a light, provides indication of voltage. The buzzer is, preferably, polarity sensitive in order to give the user of the tool or device additional flexibility when diagnosing and servicing low voltage electric circuits typically as incorporated in motor vehicles. It is noted, however, tat the circuit testing device, or kit, may be used in any environment where low voltage testing is appropriate and thus, the use of the device is not limited to the automotive or vehicle repair field. The audio buzzer and the electric light are retained within a translucent handle. They are mounted on a transportable bracket and are maintained in parallel electric array in the test circuit.
Thus, it is an object of the invention to provide a circuit testing device which works in and for circuits having a low voltage wherein the device can be used to perform multiple functions including detection of a short circuit, detection of circuit continuity remotely by a sound indicator, detection of polarity in a circuit, and investigation and determination of battery drain.
It is a further object of the invention to provide an easily manipulated circuit testing device which is manually operated and which includes various attachments to facilitate the test protocol desired by the user.
Another object of the invention is to provide a rugged and dependable circuit testing device which may be assembled and disassembled easily to permit ease of repair and replacement of parts.
Yet another object of the invention is to provide a circuit testing device which is not costly.
These and other objects, advantages and features of the invention will be set forth in the detailed description which follows.